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Unraveling the Unseen Players in the Ocean - A Field Guide to Water Chemistry and Marine Microbiology
Published on: November 5, 2014
Nitric oxide in seawater
Science (New York, N.Y.)
|February 8, 1980
Summary
Nitrite photolysis in seawater generates nitric oxide (NO). This NO rapidly cycles, indicating the presence of other seawater free radicals and making the Pacific Ocean an NO source to the atmosphere.
Area of Science:
- Oceanography
- Chemical Oceanography
- Atmospheric Chemistry
Background:
- Nitrite is a key compound in marine nitrogen cycling.
- Understanding the fate of nitrite in sunlit surface waters is crucial for marine biogeochemistry.
Purpose of the Study:
- To investigate the photolysis of nitrite and the subsequent formation of nitric oxide (NO) in seawater.
- To determine the in situ occurrence and cycling of NO in the central equatorial Pacific.
Main Methods:
- Laboratory experiments simulating natural sunlight and seawater conditions.
- In situ measurements of NO in surface waters of the central equatorial Pacific.
Main Results:
- Nitrite photolysis produced detectable NO concentrations under natural light.
- NO was rapidly consumed by a dark chemical reaction in the lab.
- In situ, NO formed during daylight and disappeared at sunset in the Pacific.
- Rapid NO cycling suggests the presence of other reactive free radicals in seawater.
Conclusions:
- Nitrite photolysis is a source of NO in sunlit surface ocean waters.
- The rapid cycling of NO indicates complex photochemical processes and the presence of free radicals.
- The central equatorial Pacific acts as a source of atmospheric nitric oxide.
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